Infield Fly

[Dakota]

At this weekend's 12U ASA JO tournament, my partner called two IF's that I would not have called. I was the BU; he had the plate. The two fly balls were not quite line drives, but were a low enough arch that I considered the fielder's ability to catch them to be more the luck of quick reflexes, particularly at 12U, and not "ordinary effort."

The book says that a line drive is not an IF. I don't judge the IF based on arch (like a SP pitch), but there are fly balls into the infield that are higher than a line drive but are still not an IF.

So, I've been thinking... how do you make the decision?